Rotary piston engine

ABSTRACT

This disclosure relates to an internal combustion engine that uses a rotary piston for overcoming the disadvantages of currently available engines. The disclosed engine is simple, and may be used in a multi-cylinder arrangement for increased power production.

United. States Patent Bernstein 1451 Dec. 26, 1972 541 ROTARY PISTON ENGINE 1,088,391 2 1914 Almy ..123/s.2s x [72] Inventor: Robert J. Ber ste n H881 Steele 1,581,148 4/1926 W1111ams ..123/8.15

Drive, Garden Grove, Calif. 92640 P E Ed W G gh rimary xaminergar eo egan [22] Sept 1970 Assistant Examiner-Alien M. Ostrager [211 App] 9 533 Attorney-Nienow & Frater v [52] US. Cl ..60/15, 123/18 R, 123/1821, 57 ABSTRACT 4l8/12,418/249 511 1111.01. ..F02b 75/32, F0212 23/04 P dlscmure relates 9 an Internal cemPustlon [58] em of Search "418/12, 244 249; 123/18 R, g1ne that uses a rotary p1ston for overcommg the disl23/8 47 821 825 39.16 advantages of currently avallable engines. The dis-' closed engine is simple, and may be used in a multi- [56] References Cited cylinder arrangement for increased power production.

' 878,543 2/1908 Krygowski ..41s/244 1,019,177 3/1912 Morton "123/823 I NVEN TOR.

ROBERT JBzeA/srE/N %BYW r mv 7 ORA/75 PATENTEB DEC 2 6 I972 SHEET 2 BF 2 FIG.5

FIG.6

v INVENTORM 055,97- J Bee/vs rev/v BY flrrawvers BACKGROUND A In the past, the most successful types of engines have been the turbine type and the piston type, each of these having many subdivisions and subclasses.

The turbine engines still have a large number of shortcomings to be cleared up, among these being (A) the necessity of racing the turbine to obtain the desired power for starting and for acceleration, (B) the criticality of the extremely close tolerances, (C) the need for materials capable of withstanding ever higher temperatures and pressures, etc. Moreover, there are indications that the turbine engine contributes appreciably to the problem of air pollution. I

The piston type engines, both gasoline and diesel, have become widely used in spite of their shortcomings. For example, it is widely acknowledged that both of these contribute to the smog problem. These piston engines must also be raced in order to develop the desired starting and accelerating power. Furthermore, these piston engines have a plurality of relatively heavy pistons that are accelerated in one direction, stopped abruptly, and then accelerated in the opposite direction (so-called simple harmonic motion). This type of motion, when used in the conventional high SYNOPSIS Broadly stated, the disclosed engine uses a two lobe combustion chamber; a flap piston being positioned in one lobe, and a rotary piston" being positioned in the second lobe; an exhaust chamber also being formed by the rotary piston. In operation, the expanding gases (formed by an explosion of a combustible mixture in the first lobe) first drive the flap piston which thereuspeed piston engine, places a great strain on the interconnections requiring extra strength linkages; and since this simple harmonic motion inherently introduces a great deal of vibration, much of the engine design effort and the actual structure of the piston engine are devoted to minimizing this vibration.

OBJECTS AND DRAWINGS It is therefore the principal object of the present invention to provide an improved internal combustion engine.

It is another object of the present invention to provide an improved rotary piston internal combustion eng ne.

It is still another object of the present invention to provide an improved engine that develops more of its power at low engine speeds.

It is a further object of the present invention to provide an improved engine that has minimal vibration.

It is a still further object of the present invention to provide an improved rotary piston internal combustion engine that reduces the smog producing components of the exhaust. I

The attainment of these objects, and others, will be realized from the following description, taken in conjunction with the drawings, of which:

FIG. 1 is a schematic view showing the beginning of the power stage;

FIG. 2 is a schematic view showing another portion of the power stage;

FIG. 3 is a schematic view showing a later portion of the power stage, and the beginning of the exhaust stage;

FIG. 4 is a schematic view showing the compression stage;

FIG. 5 is a schematic view of a four cylinder engine; and

FIG. 6 shows the interrelation of the rotary pistons of the four cylinder engine of FIG. 5.

pon drives the rotary piston by a cam action. The expanding gases then directly drive the rotary piston, which incidentally forces exhaust gases (from the previous explosion) from the exhaust chamber. The rotary piston then drives the flap piston, by means of a cam action, to compress the new charge of combustible mixture that has been introduced into the first lobe of the combustion chamber. Thus, the cylinder is now ready for another cycle.

DESCRIPTION The operating principles of my novel engine may be,

understood from the schematic representation of FIG. 1. Here a housing 10 forms a cylinder 11 that contains a standard spark plug 12 for producing an ignition spark; and also contains a standard intake valve 13 for admitting a combustible mixture of gasoline and air into a first lobe 14a of a combustion chamber. It will be noted that the combustion chamber is formed by the inner walls of housing 10, and by the upper surface 15 of an oscillatoryor flap piston 16. The reason for this designation will become apparent from a later discussion.

At the instant indicated in FIG. 1, lobe 14a of the combustion chamber is filled (charged) with a combustible mixture that had been admitted before intake valve 13 had closed. The spark plug 12 is indicated to be producing an ignition spark that ignites the combustible mixture in lobe 14a. As the combustible mixture begins to burn, or explode, the resultant gases develop an ever larger volume and pressure, and the expanding volumeof gases act on the upper surface 15 of the flap piston 16. Therefore, flap piston 16 moves angularly around its pivot pin 17, in the direction indicated by arrow 18. Thus, the explosion drives the flap piston angularly downward, developing useful power that is utilized as follows.

It will be seen from FIG. 1 that the flap piston 16 has an irregularly shaped lower surface 19, and that this irregular lower surface is in contact with the periphery of a somewhat oval-shaped rotary piston 21. The reason for this designation will also become apparent from a later discussion. As the flap piston 16, under the force produced by the expanding gases, begins to turn in the direction of arrow 18, the common but moving contact point between the flap piston 16 and the rotary piston 21 causes rotary piston 21 to rotate in a clockwise direction around its pivot pin 22 as indicated by arrow 23. At this time, the flap piston 16 and the rotary piston 21 act in a cam/cam follower manner'with the flap piston 16 camming" the rotary piston 21 into a rotary movement. It will be noted that the mechanical advantage produces a power amplification.

The above described movements of the flap piston and the rotary piston 21 continue, due to the continuously expanding gases in the combustion chamber,

a flapping movement.

until at a later instant the flap piston 16 and the rotary piston 21 appear as illustrated in FIG. 2. Here, flap directly upon surface 26 of the rotary piston, driving the rotary piston into further clockwise rotary motion. In thisway, the continuously expanding gases drive the rotary piston before them, causing the rotary piston 21 to produce power that is taken off at pivot pin 22, which is actually the crankshaft.

In FIG. 2 flap piston 16 is shown to be at the limit of its clockwise'rotation, and this limit may be established by one or more stops (not shown) in the housing, or, preferably, by having a portion of the lower surface 19 of the flap piston 16 suitably shaped to accept the perigee portion of the rotary piston 21; but even this shaping is not essential. It will be realized that as the rotary piston 21 continues to rotate clockwise under the pressure of the expanding gases, its equi-radius perigee portion will hold the flap piston 16 at the illustrated position. (See FIG. 3.)

For the purpose of simplifying the present explanation, the above explained operation was assumed to begin at a given instant when the combustion chamber of FIG. 1 was freshly charged with a fresh combustible I mixture. However, in an actual case, the assumed starting instant would have been preceededby a prior gas explosion, and the now burned-out (exhaust) gases from that prior explosion would be filling the volume (exhaust chamber 27 of FIG. 2) on the distal side of the rotary piston 21. It will also be noted that the volume of the exhaust chamber 27 is, in part, defined by the location of the leading surface 29 of the rotary piston 21, so that as the rotary piston 21 continues its clockwise rotation, its leading surface 29 progressively reduces the volume of the exhaust chamber 27. As a result, the exhaust gases in the exhaust chamber 27 are progressively forced out of the exhaust chamber, being forced to flow out through an exhaust port, or valve, 28.

FIG. 3 shows the situation at a later moment. Now, the exhaust gases from the previous explosion have been practically driven out of the cylinder; and as the rotary piston 21 continues to rotate clockwise in the direction of arrow 23, its leading surface 29 bears against the'undersurface 19 of the flap piston 16. Due to the shapes of the contacting peripheries, the clockwise rotating rotary piston 21 now cams the flap piston 16 in a counterclockwise direction indicated by arrow 31 that is opposite to its previous direction, thus causing flap piston 16 to undergo an oscillatory or At the instant indicated in FIG. 3, the intake valve 13 may be opened to introduce a new charge of a combustible mixture into the lobe 14a of the combustion chamber. i

FIG. 4 shows that, as the flap piston 16 is further camrned in a counterclockwise direction, its tip 24 soon passes wall-point 25, thus closing the throat. At

this time, the flap piston 16 begins to compress the newly admitted combustible mixture in the combustion chamber. In this way, the cylinder is readied for another cycle. I

In accordance with the above explanation, piston 16 and the rotary piston 21. take the general form of flap plates having thicknesses that are determined by the power to be developed in the cylinder. It is apparent that each of these moving members should be sealed against each other and against the inner walls of the housing, and such seals are indicated in FIG. 4 at 32, 33, 34, and 35. In actuality, however, the practical sealing problems have been solved, and the seal solutions are shown and explained in POPULAR SCIENCE, October 1969, Sensational New Mercedes I-Ias Triple-Rotor Wankel Engine and in POPULAR SCIENCE, July 1969, Tri-Dyne; Slick New Rotary Engine Could Lick the Wankel. i

It will be noted that the flap piston 16 has an upper surface 15 that is shown to be relatively flat, although this upper surface and the other surfaces of the combustion chamber may be shaped to take advantage of the well-known wave propagation principles.

FIG. 5 is a schematic cross-sectional representation of a four cylinder rotary piston engine using the principles explained above. It will be seen that housing 10a forms four cylinders 11a, 11b, 11c and 11d, although the number of cylinders may be extended in view of the power to be generated by the engine. The four rotary pistons 21a, 21b, 21c and 21d areoriented at predetermined angles relative to each other in order to provide a smooth flow of power. As shown, all of the rotary pistons have a common crankshaft 22a, so that each rotary piston applies rotary power to the crankshaft, as explained above. I

It will be recalled from the foregoing explanation that each cylinder-has a flappiston, and that these are indicated in FIG. 5 at 16a, 16b, 16c and 16d, their individual angular orientations corresponding to the angular orientations of their associated rotary pistons. The flap pistons 16 may, if desired, pivot on either a common pivot shaft or on individual bearings.

In FIG. 6, the four rotary pistons 21a, 21b, 21c and 21d are shown in a pictorial view in the same angular orientations as in FIG. 5, and are shown to be connectedto a common crankshaft 22a. I

In FIGS. 5 and 6, the first cylinder 11a is indicative of the compression stage, corresponding roughly to FIG. 1. The second cylinder 1 lb is indicative of the exhaust stage, corresponding roughly to FIG. 4. The third and fourth cylinders, 11c and 11d, are indicative of different portions of the power stage, corresponding roughly to FIGS. 2 and 3.

SUMMARY The advantages of the disclosed rotary piston internal combustion are numerous. The flap piston is relatively small and lightweight; it oscillates through a relatively small angle; its motion is of relatively small amplitude; and it is not forced to undergo high-speed simple harmonic motion. Thus, not only does it develop appreciable power, but it produces minimal vibration.

The rotary piston rotates continuously in the same direction; it has minimal acceleration and stoppings. Thus, it too produces minimal vibration.

the flap The disclosed engine tends to operate at a lower engine speed than prior art equivalent power engines, since the rotary piston produces the equivalent of a long stroke. Moreover, more power is produced at lower engine speeds than prior'art engines. Further: more, a high compression ratio is easily achieved.

The disclosed engine is also advantageous from the point of view of reduced air pollution, as may be understood from the following discussion. In the usual internal combustion engine, the still-hot exhaust gases are immediately discharged into the atmosphere where, due to their still high temperature, they readily react with various chemicals (oxygen, nitrogen, etc.) in the air, to produce smog. However, in the disclosed engine, the exhaust gases are not discharged until the next rotation of the rotary piston, and by that time they have cooled to a lower temperature that discourages the formation of smog components. 7

While the foregoing explanation has been presented in terms of a single cycle, it is obvious that subsequent cycles follow each other in continuous succession. Also, whereas the above description has been given in terms of a two-cycle operation, alternatively the engine may be operated in a four-cycle manner.

What is claimed is:

1. A rotary combustion engine comprising:

a combustion chamber having a first lobe, and a second lobe, and a throat interconnecting said first and second lobes of said combustion chamber;

a flap piston positioned in said first lobe of said combustion chamber, said flap piston having an irregularly shaped cam configurated lower surface havportion of the second lobe;

a single uni-planar rotary piston positioned in said second lobe of said combustion chamber, said rotary piston having its periphery positioned in a cam/cam follower contact with said convexly domed portion of said irregularly cam-shaped lower surface of said flap piston,

whereby when said flap piston is driven by-said expanding volume of gases resulting from said explosion occurring in said first lobe of said combustion chamber, said convexly domed portion of said irregularly shaped cam configurated lower surface of said flap piston, earns the rotary piston into rotary'motion, and the movement of said flap piston from within said first lobe into said second lobe, opens said throat so that theexpanding gases resulting from the explosion occurring in said first lobe of said combustion chamber, pass through the now-open throat to directly ,drive said rotary piston in a rotary power producing manner;

means for admitting a combustible mixture into said first lobe,

said flap piston having a uniform upper surface,

said uniform upper surface facing said means for admittin acombustible mixture, said um orm upper surface provrdmg'a means to compress a combustible mixture after its entry to the first lobe,

whereby as the leading surface of said rotary piston contacts said irregularly shaped cam configurated lower surface of said flap piston, the flap piston is cammed completely into said first lobe,

whereby compression of the combustible mixture occurs prior to its combustion;

an exhaust port positioned in said second lobe,

whereby rotation of said rotary piston causes said rotary piston to cooperate with said flap piston to form a means to force exhaust gases in said second lobe out through said exhaust port.

mam; Mon 

1. A rotary combustion engine comprising: a combustion chamber having a first lobe, and a second lobe, and a throat interconnecting said first and second lobes of said combustion chamber; a flap piston positioned in said first lobe of said combustion chamber, said flap piston having an irregularly shaped cam configurated lower surface having a convexly domed portion; the tip of said flap piston being hingedly mounted to move into said second lobe, whereby when a combustible mixture is exploded in said first lobe of said combustion chamber, the expanding gases resulting from said explosion, drive said flap piston from within the first lobe into a portion of the second lobe; a single uni-planar rotary piston positioned in said second lobe of said combustion chamber, said rotary piston having its periphery positioned in a cam/cam follower contact with said convexly domed pOrtion of said irregularly cam-shaped lower surface of said flap piston, whereby when said flap piston is driven by said expanding volume of gases resulting from said explosion occurring in said first lobe of said combustion chamber, said convexly domed portion of said irregularly shaped cam configurated lower surface of said flap piston, cams the rotary piston into rotary motion, and the movement of said flap piston from within said first lobe into said second lobe, opens said throat so that the expanding gases resulting from the explosion occurring in said first lobe of said combustion chamber, pass through the now-open throat to directly drive said rotary piston in a rotary power producing manner; means for admitting a combustible mixture into said first lobe, said flap piston having a uniform upper surface, said uniform upper surface facing said means for admitting a combustible mixture, said uniform upper surface providing a means to compress a combustible mixture after its entry to the first lobe, whereby as the leading surface of said rotary piston contacts said irregularly shaped cam configurated lower surface of said flap piston, the flap piston is cammed completely into said first lobe, whereby compression of the combustible mixture occurs prior to its combustion; an exhaust port positioned in said second lobe, whereby rotation of said rotary piston causes said rotary piston to cooperate with said flap piston to form a means to force exhaust gases in said second lobe out through said exhaust port. 